With the development of communication technology, portable electronic products such as mobile phones, handheld game machines or handheld multimedia entertainment apparatus enter people's lives. In these portable electronic products, micro-vibration motors are generally used to make system feedbacks, such as mobile phone notifications on incoming calls, game machine vibration feedbacks and the like. However, with the development trend of thin and lightweight electronic products, a variety of internal components thereof also need to adapt to this trend, and the micro-vibration motor is no exception.
Existing micro-vibration motors generally comprise an upper cover, a lower cover which forms a vibration space with the upper cover, a vibrator (including a counterweight and a permanent magnet) performing a linear reciprocating vibration in the vibration space, an elastic support connecting to the upper cover and driving the vibrator to perform a reciprocating vibration, and a coil positioned a distance below the vibrator.
In a micro-vibration motor having the above-described structure, the permanent magnet and the coil are placed perpendicularly to each other, i.e., the direction of magnetization of the permanent magnet is parallel to the axis direction of the coil, so that the magnetic lines of flux of the permanent magnet can perpendicularly pass through the coil to make the magnetic field of the permanent magnet to be utilized as much as possible. However, in a micro-vibration motor having the above-described structure, the magnetic lines of flux generated by the permanent magnet itself in the vibrator are relatively dispersed; thus the generated magnetic fields are still not adequately utilized, and correspondingly the magnetic flux passing through the coil will be relatively small, so that the acting force will be relatively small and thus affect the vibration sensing effect. When the vibrator moves to two ends, the magnetic flux passing through the voice coil in the vertical magnetization direction is also very small, thus making the vibration sensing and the linear vibration response speed of the electronic products slow and the vibration sensing small.